‘Parallel Universe’ of Life Described Far Beneath the Bottom of the Sea

Deep beneath the ocean floor off the Pacific Northwest coast, scientists have described the existence of a potentially vast realm of life, one almost completely disconnected from the world above.

Persisting in microscopic cracks in the basalt rocks of Earth’s oceanic crust is a complex microbial ecosystem fueled entirely by chemical reactions with rocks and seawater, rather than sunlight or the organic byproducts of light-harvesting terrestrial and aquatic ecosystems.

Such modes of life, technically known as chemosynthetic, are not unprecedented, having also been found deep in mine shafts and around seafloor hydrothermal vents. Never before, though, have they been found on so vast a scale. In pure geographical area, these oceanic crust systems may contain the largest ecosystem on Earth.